PMID- 9003770
OWN - NLM
STAT- MEDLINE
DCOM- 19970213
LR  - 20181113
IS  - 0261-4189 (Print)
IS  - 1460-2075 (Electronic)
IS  - 0261-4189 (Linking)
VI  - 15
IP  - 24
DP  - 1996 Dec 16
TI  - Autocatalytic polysialylation of polysialyltransferase-1.
PG  - 6943-50
AB  - Polysialic acid (PSA) is a specific and highly regulated post-translational 
      modification of the neural cell adhesion molecule NCAM. Synthesis of PSA depends 
      on the activity of a single enzyme, the polysialyltransferase-1 (PST-1), recently 
      cloned from three mammalian species. The present study was carried out to 
      investigate the catalytic mechanism of PST-1. Using a newly developed in vitro 
      assay system, we demonstrate autopolysialylation for PST-1. The synthesis of PSA 
      chains, which involved N-glycosylation sites, occurred immediately after contact 
      with the activated sugar donor CMP-Neu5Ac. In contrast to the polysialylation of 
      NCAM, where terminal sialylation in either the alpha2,3 or alpha2,6 position is 
      required, the autopolysialylation could be started in the asialo-PST-1 isolated 
      from CHO cells of the Lec2 complementation group. Pre-formed PSA chains were not 
      transferred to NCAM. Nevertheless, the autocatalytic step is likely to be a 
      prerequisite for enzymatic activity, since agalacto-PST-1 isolated from Lec8 
      cells was functionally inactive. Our data describe a novel route of autocatalytic 
      maturation of a glycosyltransferase and thereby provide a new basis for studies 
      aimed at elucidating and influencing the catalytic functions of PST-1.
FAU - Muhlenhoff, M
AU  - Muhlenhoff M
AD  - Institut fur Medizinische Mikrobiologie, Medizinische Hochschule Hannover, 
      Germany.
FAU - Eckhardt, M
AU  - Eckhardt M
FAU - Bethe, A
AU  - Bethe A
FAU - Frosch, M
AU  - Frosch M
FAU - Gerardy-Schahn, R
AU  - Gerardy-Schahn R
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - England
TA  - EMBO J
JT  - The EMBO journal
JID - 8208664
RN  - 0 (Neural Cell Adhesion Molecules)
RN  - 0 (Recombinant Proteins)
RN  - 0 (Sialic Acids)
RN  - 0 (Staphylococcal Protein A)
RN  - 0 (polysialic acid)
RN  - EC 2.4.99.- (CMP-N-acetylneuraminate-poly-alpha-2,8-sialosyl sialyltransferase)
RN  - EC 2.4.99.- (Sialyltransferases)
SB  - IM
MH  - Animals
MH  - CHO Cells
MH  - Catalysis
MH  - Cricetinae
MH  - Glycosylation
MH  - Kinetics
MH  - Neural Cell Adhesion Molecules/metabolism
MH  - Recombinant Proteins/metabolism
MH  - Sialic Acids/*metabolism
MH  - Sialyltransferases/*metabolism
MH  - Staphylococcal Protein A/metabolism
PMC - PMC452520
EDAT- 1996/12/16 00:00
MHDA- 1996/12/16 00:01
PMCR- 1997/12/16
CRDT- 1996/12/16 00:00
PHST- 1996/12/16 00:00 [pubmed]
PHST- 1996/12/16 00:01 [medline]
PHST- 1996/12/16 00:00 [entrez]
PHST- 1997/12/16 00:00 [pmc-release]
PST - ppublish
SO  - EMBO J. 1996 Dec 16;15(24):6943-50.